Staple



Feb. 27, 1940. w. M. STONE 2,191,869

STAPLE Filed May 9, 1938 ffm/wins.

Patented Feb. 27, 1940 UNITED STATES PATENT vori-ICE STAPLE Warren M.Stone, Camden, N. J.

Application May 9, 1938, Serial No. 206,708 s claims. (c1. ca -4) Theobject of the invention is to provide a staple for securing together aplurality of layers of material or for securing one or more .layers ofmaterial to a penetrable body. A staple of this character comprises theusual crown and end legs, the latter being adapted to penetrate theelements intended to be secured together. In case the staple is used tosecure together a plurality of layers of material, the crown of theapplied staple overlies the top layer while the legs are bent inwardtoward each other under the bottom layer. In case the sta-ple isI usedto secure one or more layers of material to a thick penetrable body, thecrown will overlie the top layer and, without bending, penetrate thesaid body. The

staple may be made of various sizes and is adapted to a variety ofspecific applications.

The above specified characteristics of my improved staple are thosewhich characterize conventional staples. The ordinary staple, however,cannot be relied upon to operate satisfactorily under all conditions ofuse and is not intended `or adapted for certain uses for which myimproved staple is intended andl adapted. For example, When ordinarystaples of small size are used for securing together certain materialsresistant to penetration, the legs of the staple are apt to jam or clog,the ends of the legs adjacent to the crown being forced toward eachother and the crown buckling downward, making the fastening insecure orineffective. Again, when ordinary staples are used to fasten together amultiplicity of flexible sheetsV (e. g., paper) of easily penetrablematerial, the anvil of the stapling machine, which guides the free endsof the legs inward, will often cause the legs to be deflected beforecomplete penetration, cutting or tearing the flexible material. Againthe ordinary staple is ineffective to penetrate thin metal sheets, forwhich purpose a staple of special construction must be provided. Myimproved staple is open to none of the foregoing objections and hasother special advantages which are hereinafter explained.

Several embodiments of the invention are shown in the accompanyingdrawing:

Fig. 1 is a perspective view of a staple made by bending a strip ofmetal of permissibly uniform thickness and width.

Fig. 2 is a perspective view of a staple which may be made from a blockby fprging or -any other suitable metal-working operation.

Fig. 3 is a sectional elevational view of the staple of Fig. 2.

Fig. 4 is a plan view of half of the staple oi.'

Figs. 2 and 3 associated with the guide (shown in cross-section) of astapling machine.

Fig. 5 is a view, similar to Fig. 3, of a modification.

Fig. 6 is a view, similar to Fig. 4, showing the application of thestaple of Fig. 5 to the guide of a stapling machine.

The staple of Fig. 1 is formed by taking a strip of material of uniformwidth and thickness and of a width exceeding its thickness and bendingits central portion at right angles to its end portions to form arelatively narrow crown a .and relatively wide legs b, b. i

The staple of Figs. 2 and 3 may be formed by forging or swaging a longblock of material to form a relatively narrow crown c and relativelywide legs d, d.

In Figs. 1, 2 and 3 the transverse extension of the legs is beyond bothsides of the crown. The staple of Fig. 5 is similar to that of Fig. 3but differs therefrom in that the legs f. f are laterally offset fromthe crown e on one side only of the latter.

It will be understood that the staple of Fig. 1 may be similarlymodified to produce a staple the legs of which are offset from one sideonly of the crown.

Any of the staples may be provided with legs tapering to sharp edges, asshown in Figs. 2, 3 and 5.

The form of the staple of Fig. 3 (and also of Fig. l) is such as toadapt it for use in a stapling machine provided with guides gwhichembrace the legs of the staple on all four faces, and at all fourcorners, of each leg. It is therefore impossible to bend the legs duringpenetration, the governing basic principle being the same as that whichenables a needle, embedded in a supporting layer of cork, to be heldfrom deflection While being driven through a considerable thickness ofmetal. The same advantage inheres in the staple of Fig. 5, which is soshaped as to adapt it for use in a stapling machine provided with guidesh which enclose the legs of the staple on all four sides and at three ofthe four corners.

It will thus be clear that a staple embodying my invention cannot jam orclog during penetration. No part of the leg can bend (if the staple isused for securing together a plurality of layers of material) untilafter such part has completed its penetration and therefore the crowncannot buckle. After the stapling operation is completed, the crownnecessarily lies straight over the upper layer, the adjacent part of theleg extends at right angles to the crown, and the projectlng ends of thelegs extend inwardly toward each other in parallelism with the crown.

Moreover, if the staple is used to secure together a number of sheets ofpaper, there cannot be any tearing, cutting or shredding of the paper,due to inward. deiiection of any part of a leg, be' fore it hascompleted penetration of all the sheets.

By making the crown height dimension the greater dimension in crosssection and by onsetting the legs as described and shown with theirsmaller transverse dimensions parallel with the longitudinal extensionof the crown, the stinness of the crown is enhanced and the strength ofthe staple as a whole is increased, while at the same time the weight ofmetal in the'staple may be safely less than that of the conventionalstaple of comparable size.

In the stapling machine, the guides g or h should be of internaldimensions slightly greater than the external dimensions of the legs, soas to provide a tolerance or clearance between the staple legsv and thewalls of the guides.v 'I'his permits distortion, or lateral now withenlargement of cross section, of metal under the driving pressure. f

,It will be understood' that my invention may be embodied not only instaples which are formed separately before insertion in the staplingmachine but also in staples which, in the stapling machine itself, arecut to length from a continuous strip of metal and bent to shape.'I'hese alternative methods of forming staples are known in the art.

What I claim and desire to protect by Letters Patent is:

I. A staple comprising a crown and end legs, the crown being of greaterthickness vertically than laterally and the legs being of greaterthickness in the transverse direction of the staple than in a directionparallel to the longitudinal extension of the crown and of substantiallygreater thickness in the transverse direction of the staple than thelateral thickness of the crown.

2. A staple comprising a crown -and end legs,

all of similar and substantially equal oblong cross section, the greaterthickness of the crown being in the direction of penetration and thegreater thickness or the lees being e: riant longitudinal extension ofthe staple.

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3. A staple comprising 'a continuous strip of I metal the centralportion and opposite end portions of which are all comparatively wideand thin. the greater cross-sectional dimensions of che end portionsbeing et right angles ce the 'n greater cross-sectional dimension ofthecentral portion, the metal strip being bent at the junction of thecentral portion and the end portions to laterally onset with respect tothe sides of the -crow-n, thereby imparting maximum strength to thecrown and enabling the legs to' be .guided ured' in either direction atright angles to its direction of extension, the legs being onsetlaterally from the adjacent ends of the crown, each leg from itsjunction with the crown downward being onset laterally from at least oneside oi' the crown so as to adapt said legs, before and duringpenetration and until penetration is substantially completed, to beguided at all four sides and at not less than three corners.

5. A staple comprising a crown and end legs, the length of the crownbetween the legs being multiple times the thickness of the crownmeasured in either direction at right angles to its direction ofextension, each end leg being onset laterally from both sides of thecrown so as to adapt said legs, before and during penetration and untilpenetration is substantially completed, to be guided at all four sidesand at all four corners.

6. A staple comprising a crown and end legs, all oi' oblong crosssection, the greater thickness ,of the crown being in the direction ofpenetration and the greater thickness of the legs being at right anglesto the longitudinal extension of the staple, the legs being onsetlaterally from the ends of the crown.

'l0 form a staple comprising a crown which is thicker f v in thedirection of penetration and legs which are WARREN M. STONE.

